silk gauze
絽 centers on a specific type of silk fabric: a thin, open-weave silk gauze.
絽 combines 糸 (thread/silk) with 吕, which likely contributes the sound. The character specifically denotes a type of silk gauze.
The left side is 糸 (thread), and the right side 吕 looks like two open mouths or a loose grid. Picture threads woven into an open, airy gauze fabric.
For ロ, imagine a roll of silk gauze: roll -> ロ, and the fabric is thin and airy.
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